CVE-2024-1731: Rymera Auto Refresh PHP Object Injection

CVE-2024-1731 Overview

The Auto Refresh Single Page plugin for WordPress contains a PHP Object Injection vulnerability affecting all versions up to and including 1.1. The flaw stems from unsafe deserialization of untrusted input from the arsp_options post meta option. Authenticated attackers with contributor-level access or higher can inject arbitrary PHP objects into the application. The vulnerable plugin itself does not ship a Property-Oriented Programming (POP) chain, but the presence of any additional plugin or theme containing a usable gadget chain can escalate the impact to arbitrary file deletion, sensitive data disclosure, or remote code execution.

Critical Impact

Contributor-level users can inject PHP objects that, when paired with a POP chain from another installed plugin or theme, lead to arbitrary file deletion, data exfiltration, or code execution on the WordPress host.

Affected Products

• Rymera Auto Refresh Single Page plugin for WordPress, versions up to and including 1.1
• WordPress sites where contributor-or-higher accounts exist and the plugin is active
• WordPress installations that also host any plugin or theme exposing a POP gadget chain

Discovery Timeline

• 2024-03-05 - CVE-2024-1731 published to the National Vulnerability Database
• 2026-06-17 - Last updated in NVD database

Technical Details for CVE-2024-1731

Vulnerability Analysis

The vulnerability is an Insecure Deserialization flaw classified under [CWE-502]. The plugin calls PHP's unserialize() on attacker-controllable data stored in the arsp_options post meta field. Because unserialize() reconstructs PHP objects and invokes magic methods such as __wakeup() and __destruct(), an attacker who controls the serialized payload can instantiate arbitrary classes that are already loaded in the WordPress runtime.

The plugin alone does not contain classes with dangerous magic methods, so exploitation on a bare install stops at object instantiation. In real-world WordPress deployments, however, dozens of plugins and themes are typically loaded in the same process. Any one of those extensions can supply a POP chain, turning the object injection into file deletion, arbitrary file read, SQL injection, or remote code execution.

Root Cause

The root cause is direct passing of stored post meta content into unserialize() without integrity validation or type constraints. Post meta values are writable by any user who can edit the associated post, which includes the contributor role. WordPress does not sanitize serialized structures, so the plugin must treat this data as untrusted.

Attack Vector

An authenticated attacker with contributor privileges edits a post to which they have access and sets the arsp_options post meta value to a crafted serialized PHP object payload. When the plugin later reads that meta value and deserializes it, the injected object is materialized in memory. If a POP gadget chain is reachable through any other installed component, the attacker triggers the chain to reach the desired sink such as file_put_contents, unlink, or eval-equivalent execution paths.

No verified public exploit code is available. Refer to the Wordfence Vulnerability Report and the WordPress Plugin Code Reference for technical specifics on the vulnerable call site.

Detection Methods for CVE-2024-1731

Indicators of Compromise

• Post meta entries with the key arsp_options whose values begin with PHP serialization markers such as O:, a:, or s: and reference class names not defined by the Auto Refresh Single Page plugin
• Unexpected creation, modification, or deletion of files under wp-content/, wp-includes/, or the WordPress root by the PHP-FPM or web server user
• New administrator accounts, altered wp_options rows, or scheduled cron entries created shortly after contributor account activity
• PHP error log entries referencing __wakeup, __destruct, or class autoloading failures tied to requests processed by the plugin

Detection Strategies

• Query the wp_postmeta table for meta_key = 'arsp_options' and inspect values for serialized object markers or unexpected class references
• Alert on writes to post meta keys by contributor-role users where the payload matches a PHP serialization signature
• Correlate contributor authentication events with subsequent filesystem writes, outbound HTTP requests, or spawned shell processes from the web server

Monitoring Recommendations

• Ingest WordPress audit logs, PHP error logs, and web server access logs into a centralized analytics platform for correlation across identity and process telemetry
• Baseline the set of PHP classes and magic methods invoked during normal plugin operation and alert on deviations
• Track post edits by contributor accounts, focusing on high-frequency meta updates and payload size anomalies

How to Mitigate CVE-2024-1731

Immediate Actions Required

• Update the Auto Refresh Single Page plugin to a version later than 1.1 as soon as a fixed release is published by the vendor; deactivate and remove the plugin in the interim
• Audit contributor and author accounts, disable unused accounts, and enforce strong authentication for all editorial roles
• Review wp_postmeta for existing arsp_options values containing serialized objects and remove or quarantine suspicious entries
• Perform an integrity review of installed plugins and themes to identify components that expose exploitable POP gadget chains

Patch Information

At the time of NVD publication, no fixed version was listed in the advisory. Monitor the WordPress Plugin Code Reference and the Wordfence Vulnerability Report for updated version guidance. Until a patch is available, removing the plugin is the reliable remediation.

Workarounds

• Uninstall the Auto Refresh Single Page plugin and replace it with a maintained alternative
• Restrict the contributor role using an access control plugin so that meta editing is not available to untrusted users
• Apply a web application firewall rule that inspects and blocks PHP serialization patterns in requests targeting post edit endpoints
• Enforce least-privilege filesystem permissions so that the PHP process cannot modify plugin, theme, or core files

# Configuration example: remove the vulnerable plugin from a WordPress install
wp plugin deactivate auto-refresh-single-page
wp plugin delete auto-refresh-single-page

# Identify residual serialized payloads in post meta
wp db query "SELECT post_id, meta_value FROM wp_postmeta WHERE meta_key = 'arsp_options';"